Ugh! Sig Jig screwup

If you hammer on the rails directly, trying to create a sharper bend that touches the top of the jig, you will do two things... you will make the rails too thin, and the sharp inside corner will create a point where a stress fracture can form.

If it helps understand what happens, take a stick of chewing gum (a reasonably ductile and malleable stand-in for steel.) Fold it in two. The outside surface of the fold will develop a bunch of little cracks, where the gum couldn't stretch around the tight corner. Now, unfold the stick... it will snap into two pieces right at the inside crease of the fold. The structure of the gum got all jumbled up at the point of the fold and can't stretch back to it's original flat shape.

While chewing gum isn't steel, what happens in steel works the same way. It just takes a lot more force. A lot of materials behave this way. Plastics, Aluminum, Copper, Tin... they all accumulate damage to the structure when mechanically bent at sharp angles. Some fail immediately or during the bend (cast iron or aluminum will just snap) while others like sheet steel will eventually fail when subjected to multiple cycles of trying to wiggle the bend. Which is what the slide does to the rails every time the pistol is fired.

Now, if you use the plug and jig to do the bending of the MUP rails, you don't get the sharp inside corner, so the rails are stronger overall. And more importantly, the plug and jig already account for the radius of the bend they will create... so the rail surfaces the slide ride on end up in the same plane and the correct height above all the parts inside the MUP that make it work. There is no need to ever hammer on the rails directly.

If you hammer on the plug in the process of bending the rails, yeah, you leave hammer marks on the plug. But that is just cosmetic damage to the jigs. Doesn't hurt the MUP inside the jig one little bit. Just don't ever hammer on the MUP itself. ;)
 
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The jig shipped today. JFC.... It took months!
 
Good thing, any later and it would have sat on your front porch for 6 months!
Yes. It should arrive in a couple of days. But I don't have time to start that project now. It will have to wait.
 
I received my 2 MUPS and have been waiting for the jig. I contacted GG to ask for a status and they had no order history on my account for it. I don't think they screwed up. I must have gotten distracted and exited before completing the checkout. I ordered the MUPS separately from the jig.

So I placed a new order. It may take 6 weeks to get it. Messes up my plans, but it's my own fault.

I must say GG were very prompt and thorough in answering my email inquiry. Next day response.
Where did you pur have the fcu and jig
 
Where did you pur have the fcu and jig
You won't get an answer since BL is "unretired" and offline for 6 months or so.

ETA: I see Bobster was a bit quicker on the reply. ;)
 
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You guys know of anywere to get a fcu and the jig as far as company's that have them
 
Check our vender list. I try to keep it updated as I see members post information. Parts come in and out of stock. US Patriot Armory seems to have 80% goods in stock these days including sig products. Get that mup-1 and jig while they last
 
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